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Interview Questions
Practice 9403 coding, system design and machine learning questions from 546 companies, sorted by role, topic and interview round. Every question has step-by-step hints, a code runner that supports 8 languages and an AI mentor; members also get the full solution walkthrough.
- 9403
- Questions
- 546
- Companies
- 11
- Topics
- 8
- Languages
Showing 61–90 of 3640 results
- AirbnbMediumMachine Learning EngineerDesign photo and listing quality models
This question tests the end-to-end design of a machine learning system to evaluate the quality of listing photos and overall listing attractiveness to improve search ranking and conversion.
Machine LearningOnsiteComputer VisionRanking SystemsFeature Engineering - AirbnbHardSoftware EngineerDesign rental watchlist and notification system
This question evaluates system architecture and scalability competencies, including data modeling for date-range watchlists, event-driven notification pipelines, time-zone and DST handling, consistency and concurrency semantics, idempotency, sharding/caching strategies, and privacy/analytics considerations.
System DesignOnsite - AirbnbHardSoftware EngineerDesign scalable notification system
Airbnb's onsite system design round asks you to design a notification system that delivers email, SMS, and push messages to millions of guests, hosts, and employees, supporting both event-triggered sends and large batch campaigns. A complete answer covers requirements and scale math, architecture and data flow for both modes, the data model and API, templating, user preferences and compliance, prioritization, deduplication and idempotency, retries and failover, scaling and backpressure, observability, and cost. This walkthrough gives a corrected end-to-end reference answer for every part, including the trade-offs interviewers probe.
System DesignOnsite - AirbnbHardSoftware EngineerDetect overlap of two linked lists with cycles
This problem tests your ability to detect if two linked lists merge, specifically when they may contain cycles, by requiring logic to identify loop entry points and intersection nodes.
Coding & AlgorithmsOnsiteLinked ListTwo PointersCycle Detection - AirbnbMediumMachine Learning EngineerDiscuss ML Project Tradeoffs
This question evaluates a candidate's skills in model selection, trade-off analysis between precision, recall, latency and infrastructure cost, threshold tuning, reconciliation of offline versus online metrics, and comparative understanding of recommendation models within the Machine Learning domain.
Machine LearningOnsite - AirbnbMediumData EngineerEstimate Page-Visit Duration from the Next User Event
Implement logic to compute user page-visit durations based on adjacent event timestamps, deterministically resolving ties and handling boundary conditions for terminal events.
Data Manipulation (SQL/Python)Onsitepythonsqldata-manipulation - AirbnbMediumMachine Learning EngineerExplain ML Project Milestones, Scope, and Conflict
Explain an ML project through scope decisions, measurable milestones, stakeholder conflict, online readiness, and evidence-based changes to the plan.
Behavioral & LeadershipOnsite - AirbnbMediumData EngineerFind Hosts Meeting Listing, Rating, and Review-Coverage Rules
Tests the ability to write a SQL query performing multi-table aggregations, date-windowed conditional logic, and host-level qualification filtering across listing counts, average ratings, and recent review coverage.
Data Manipulation (SQL/Python)Onsitesqlaggregationconditional-logic - AirbnbMediumData EngineerFind Users with Seven Consecutive Impression Days
Tests your ability to identify consecutive calendar-day activity streaks in PostgreSQL using window functions, date arithmetic, and deduplication.
Data Manipulation (SQL/Python)Onsitesqlpostgresqlwindow-functions - AirbnbMediumSoftware EngineerFind palindrome-forming string pairs
This question evaluates string-processing and algorithmic design skills, including knowledge of efficient lookup data structures, palindrome properties, handling of edge cases, and time/space complexity analysis.
Coding & AlgorithmsOnsite - AirbnbMediumSoftware EngineerFind smallest permutation under constraints
This problem tests your ability to manipulate digits and understand greedy strategies to construct the smallest possible number after applying specific constraints.
Coding & AlgorithmsOnsiteGreedyRecursionStrings - AirbnbHardSoftware EngineerFlatten a Nested Integer List
Flatten an arbitrarily deep mixture of integers and lists while preserving left-to-right order. The challenge emphasizes an iterative stack solution that handles empty lists, very deep nesting, and up to 200,000 nodes without mutating the input.
Coding & AlgorithmsOnsite - AirbnbMediumMachine Learning EngineerGenerate Customer-Support Instructions from Company Policies
Design a policy-grounded support RAG system with ordered instructions, applicability checks, procedural evaluation, citations, and version-aware debugging.
ML System DesignOnsite - AirbnbHardSoftware EngineerHow do you conduct a code review exercise?
This question tests a software engineer's ability to conduct structured, high-signal code reviews under time pressure and limited context. It evaluates judgment in prioritizing correctness issues over style, communicating feedback clearly, and handling ambiguity — core competencies in software engineering fundamentals interviews.
Software Engineering FundamentalsOnsite - AirbnbMediumSoftware EngineerImplement a reservation widget with pricing
This question evaluates skills in frontend component state design, data modeling, pricing computation, validation logic, error handling, and API integration for a lodging reservation widget.
Software Engineering FundamentalsOnsite - AirbnbHardSoftware EngineerImplement retry wrapper and interdependent validators
This question evaluates a candidate's competence in building robust asynchronous utilities and form validation logic, covering retry/backoff strategies, error classification, per-attempt and overall timeouts, cancellation via AbortSignal, observable retry hooks, cross-field validators, state management, and accessibility considerations in JavaScript/TypeScript web applications. Category: Other / Miscellaneous; domain: web development and systems reliability in JavaScript/TypeScript; it is commonly asked because it probes both conceptual understanding of retry semantics, cancellation and validation constraints and practical implementation skills related to API ergonomics, error propagation, composable validators, and performance trade-offs.
Software Engineering FundamentalsOnsite - AirbnbMediumSoftware EngineerMaximize profit from non-overlapping jobs
This question evaluates proficiency in weighted interval scheduling, dynamic programming concepts, and the use of efficient data structures for large-scale scheduling problems, including handling duplicate times, large reward values, and memory constraints.
Coding & AlgorithmsOnsite - AirbnbHardSoftware EngineerMaximize sum with no adjacent tree nodes
This problem tests your ability to use tree-based dynamic programming to solve an optimization challenge where you must select a subset of nodes with no two being adjacent, while maximizing the sum of their values.
Coding & AlgorithmsOnsiteTree DPRecursionDFS - AirbnbMediumMachine Learning EngineerMinimize exact layover bookings
This problem tests your ability to use dynamic programming to determine if a specific target sum can be achieved using a subset of given item values and how to find the minimum subset size that hits that target.
Coding & AlgorithmsOnsiteDynamic ProgrammingOptimizationAlgorithms - AirbnbMediumSoftware EngineerPrioritize consumer product opportunities
This question evaluates a candidate's ability in product strategy, data-driven user research, metric design, and prioritization within the product/decision-making domain for a consumer mobile application.
Behavioral & LeadershipOnsite - AirbnbMediumMachine Learning EngineerRank Home Search Results Without a Text Query
Design a home-search ranker without query text, covering structured intent, training bias, cold start, online evaluation, and production debugging.
ML System DesignOnsite - AirbnbMediumMachine Learning EngineerRedact Document Phrases with Simultaneous Replacement
Redact document phrases with a replacement map, whole-word matching, longest-match overlap rules, and one-pass replacement of original text.
Coding & AlgorithmsOnsite - AirbnbMediumSoftware EngineerRender Wrapped Paragraphs Inside One Text Box
Implement a text formatting utility that wraps multiple paragraphs at distinct per-paragraph widths and renders them inside a single, uniformly padded ASCII border box.
Coding & AlgorithmsOnsiteStringGreedyImplementation - AirbnbMediumSoftware EngineerReview Python geodata code
This question evaluates proficiency in Python code review and geolocation data-processing, including competencies in readability, correctness, performance optimization, and architectural scalability.
Coding & AlgorithmsOnsite - AirbnbMediumMachine Learning EngineerSolve Decimal Coin Change
This question evaluates proficiency in dynamic programming for coin-change problems and competency in numerical precision and safe handling of decimal monetary values in algorithmic implementations.
Coding & AlgorithmsOnsite - AirbnbMediumSoftware EngineerSolve Linked-List and Iterator Problems
This question evaluates proficiency in linked-list pointer reasoning, cycle detection and shared-reference identification, as well as iterator design for round-robin merging, testing data-structure manipulation, iterator interfaces, and complexity analysis within the Coding & Algorithms domain.
Coding & AlgorithmsOnsite - AirbnbHardSoftware EngineerSolve a Two-by-Three Sliding Puzzle
Find the minimum moves needed to solve a 2-by-3 sliding puzzle, or report that the target is unreachable. Model each arrangement as a compact graph state, generate legal swaps involving the blank, and use breadth-first search without revisiting configurations.
Coding & AlgorithmsOnsite - AirbnbMediumSoftware EngineerSolve palindrome pairs and key path
This pair of problems evaluates proficiency with string-processing algorithms and advanced data structures for matching, alongside state-space graph search techniques and state-encoding strategies.
Coding & AlgorithmsOnsite - AirbnbMediumMachine Learning EngineerWhy Airbnb and what matters most
This question evaluates a candidate's alignment with organizational values, authenticity of motivation, and ability to articulate personal causes along with concrete actions that demonstrate impact and priorities.
Behavioral & LeadershipOnsite - AirtableMediumSoftware EngineerCount business days excluding holidays
This problem tests date manipulation skills and the ability to efficiently calculate working day durations while accounting for dynamic holiday schedules.
Coding & AlgorithmsOnsiteAlgorithmsDate-TimeOptimization
Airbnb
Airtable